Britain's Prince Charles talks to a musician next to his wife Camilla, Duchess of Cornwall, as they visit a traditional wine tavern (Heuriger) in Vienna, Austria, April 6, 2017. REUTERS/Heinz-Peter Bader

Britain's Prince Charles talks to a musician next to his wife Camilla, Duchess of Cornwall, as they visit a traditional wine tavern (Heuriger) in Vienna, Austria, April 6, 2017. REUTERS/Heinz-Peter Bader